Wireless module

ABSTRACT

The wireless module according to the present invention includes a wireless IC chip for processing transmission/reception signals, a substrate on which the wireless IC chip is mounted, an antenna provided on the substrate, and a plurality of terminals extending off from the substrate in an in-plane direction of the substrate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a wireless module.

2. Description of the Related Art

When used, wireless modules for transmitting and receiving radio signalsare mounted on a mount object such as a circuit board. The wirelessmodule disclosed in Patent Document 1 (see e.g. JP-A-2005-294885)includes a substrate, an antenna as a transmitter-receiver provided onthe substrate, and a transmitting/receiving device (wireless IC chip)mounted on the substrate. The antenna is electrically connected to thewireless IC chip. The substrate has a principal surface and a reversesurface facing away from the principal surface. The antenna and thewireless IC chip are arranged on the principal surface. The wirelessmodule is surface-mounted on the obverse surface of the mount object,with the reverse surface of the substrate facing the mount object.

Since the conventional wireless module is designed to besurface-mounted, it requires a relatively large space for mounting.Further, to prevent degradation of communication quality, insurface-mounting the wireless module on a mount object, other electroniccomponents cannot be mounted on the reverse surface of the mount objectat the region corresponding to the antenna of the wireless module. Sucha limitation leads to waste of space.

SUMMARY OF THE INVENTION

The present invention has been conceived under the above-describedcircumstances. It is therefore an object of the present invention toprovide a wireless module that realizes space saving in mounting.

According to the present invention, there is provided a wireless modulecomprising a wireless IC chip for processing transmission/receptionsignals, a substrate on which the wireless IC chip is mounted, atransmitter-receiver at least a part of which is disposed on thesubstrate, and a plurality of terminals extending from the substrate inan in-plane direction of the substrate.

In a preferred embodiment of the present invention, the substrate has acontour including a first edge extending in a second directionperpendicular to a first direction corresponding to the thicknessdirection of the substrate. The terminals are arranged along the firstedge, and each of the terminals extends from the first edge toward afirst side in a third direction perpendicular to both of the first andthe second directions.

In a preferred embodiment of the present invention, thetransmitter-receiver includes a first antenna provided on a firstsurface of the substrate which faces to a first side in the firstdirection.

In a preferred embodiment of the present invention, the contour of thesubstrate includes a second edge spaced apart from the first edge in thethird direction and parallel to the first edge. The first antenna isarranged at a position offset toward the second edge in the thirddirection.

In a preferred embodiment of the present invention, the contour of thesubstrate includes a third edge and a fourth edge each of which isconnected, at their ends, to the first edge and the second edge, and thethird and the fourth edges are spaced apart from each other in thesecond direction and parallel to each other. The transmitter-receiverincludes a second antenna arranged at a position offset toward the thirdedge in the second direction.

In a preferred embodiment of the present invention, the first antenna isarranged at a position offset toward the fourth edge in the seconddirection.

In a preferred embodiment of the present invention, the first antennaand the second antenna have different radio wave directivities.

In a preferred embodiment of the present invention, each of theterminals is bent so that a region from an intermediate portion to theend extends in the first direction.

In a preferred embodiment of the present invention, the end of each ofthe terminals faces to a second side in the first direction.

In a preferred embodiment of the present invention, the wireless IC chipis mounted at one of a first region of the first surface of thesubstrate and a second region of a second surface opposite to the firstsurface of the substrate, where the first region excludes the region inwhich the transmitter-receiver is arranged, and the second regionoverlaps the first region as viewed in the first direction. Anelectronic device is mounted at the other one of the first region andthe second region.

In a preferred embodiment of the present invention, thetransmitter-receiver includes a third antenna projecting from the firstedge of the substrate toward a first side in the third direction.

In a preferred embodiment of the present invention, the third antenna isbent so that a region from an intermediate portion to the end thereofextends in the first direction.

In a preferred embodiment of the present invention, the contour of thesubstrate includes a second edge spaced apart from the first edge in thethird direction and parallel to the first edge. The transmitter-receiverincludes a fourth antenna projecting from the second edge toward asecond side in the third direction.

In a preferred embodiment of the present invention, each of theterminals is bent so that a region from an intermediate portion to theend extends in the first direction.

In a preferred embodiment of the present invention, the wireless modulefurther comprises a resin coating covering the substrate and thewireless IC chip.

In a preferred embodiment of the present invention, the wireless modulefurther comprises a resin coating covering the substrate and thewireless IC chip, and the third antenna is exposed from the resincoating.

In a preferred embodiment of the present invention, the wireless modulefurther comprises a case covering the wireless IC chip.

In a preferred embodiment of the present invention, the wireless modulefurther comprises a connector provided on the substrate and connected tothe wireless IC chip via a transmission path for transmission/receptionsignals.

According to this arrangement, mounting of the wireless module on amount object is performed by connecting to the mount object the ends ofthe terminals extending from the substrate in the in-plane direction ofthe substrate. This arrangement saves space in mounting the wirelessmodule.

Other features and advantages of the present invention will become moreapparent from detailed description given below with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view, partially in section, showing a first embodimentof a wireless module according to the present invention;

FIG. 2 is a left side view, partially in section, of the wireless moduleshown in FIG. 1;

FIG. 3 is a view corresponding to FIG. 2, showing a second embodiment ofa wireless module according to the present invention;

FIG. 4 is a front view, partially in section, showing a third embodimentof a wireless module according to the present invention;

FIG. 5 is a front view, partially in section, showing a fourthembodiment of a wireless module according to the present invention;

FIG. 6 is a left side view, partially in section, of the wireless moduleshown in FIG. 5;

FIG. 7 is a view corresponding to FIG. 2, showing a fifth embodiment ofa wireless module according to the present invention; and

FIG. 8 is a view corresponding to FIG. 2, showing a sixth embodiment ofa wireless module according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention are described below withreference to the accompanying drawings.

FIGS. 1 and 2 show a first embodiment of a wireless module according tothe present invention. The wireless module 101 of this embodimentincludes a substrate 200, a wireless IC chip 300, antennas 410, 420 as atransmitter-receiver, electronic devices 500, a plurality of leadterminals 600 and a resin coating 700. The wireless module 101 is anelectronic component to be mounted on a mount object such as a circuitboard.

The substrate 200 is an insulating substrate made of e.g. glass epoxyresin and rectangular as a whole. The contour of the substrate is madeup of two pairs of parallel edges (four edges), i.e., a first through afourth edges 211-214. The first edge 211 and the second edge 212, whichare parallel to each other, extend in the direction y perpendicular tothe direction x corresponding to the thickness direction of thesubstrate 200. The third edge 213 and the fourth edge 214, which areparallel to each other, extend in the direction z perpendicular to bothof the direction x and the direction y and connected to the first edge211 and the second edge 212 at the ends.

The substrate 200 has a wiring pattern (not shown) formed on it. Thewiring pattern is made of a highly conductive material such as Cu. Thewireless IC chip 300, the electronic devices 500 and the terminals 600are electrically connected to each other appropriately via the wiringpattern.

The antennas 410 and 420 are provided on the first surface 200 a of thesubstrate 200, which is the surface on the first side in the thicknessdirection (direction x). In this embodiment, the antennas 410, 420 aree.g. a pattern antenna and formed along with the wiring pattern on thesubstrate 200. The antenna 410 is arranged at a position offset towardthe second edge 212 in the direction z and elongated in the direction y.The antenna 410 is also offset toward the fourth edge 214 in thedirection y. The antenna 420 is arranged at a position offset toward thethird edge 213 in the direction y and elongated in the direction z.

Each of the antennas 410 and 420 is connected to the wireless IC chip300 via a transmission path (not shown) for transmission/receptionsignals. The transmission path is a portion through whichtransmission/reception signals pass and made of e.g. a metal having arelatively low resistance. The transmission path may be provided by apart of the wiring pattern. Alternatively, when the substrate 200 is amultilayer substrate, the transmission path may be provided by a metalfilm pattern formed on the multilayer substrate.

The wireless IC chip 300 is provided for processingtransmission/reception signals of predetermined frequencies and includesa predetermined signal processing circuit. The wireless IC chip 300 ismounted on the first surface 200 a on the first side of the substrate200. The wireless IC chip 300 is arranged in a first region 201 of thefirst surface 200 a, which excludes the region in which the antennas410, 420 are arranged.

The electronic devices 500 are semiconductor devices including e.g. acontrol IC for controlling the entirety of the wireless module 101, achip resistor or a capacitor. The electronic devices 500 aresurface-mounted on the first surface 200 a of the substrate 200 and asecond surface 200 b opposite to the first surface 200 a. Specifically,the electronic devices 500 are mounted in the first region 201 of thefirst surface 200 a and in the second region 202 of the second surface200 b which overlaps the first region 201 as viewed in the thicknessdirection (the direction x).

The terminals 600 are provided for performing signal exchange with e.g.the circuit board on which the wireless module 101 is mounted. Eachterminal 600 is made of e.g. Cu, Ni or alloys of these and projects fromthe substrate 200. In this embodiment, the terminals 600 extend in anin-plane direction of the substrate 200. Specifically, the terminals 600are arranged along the first edge 211 of the substrate 200, and each ofthe terminals extends from the first edge 211 toward a first side in thedirection z.

The resin coating 700 covers the substrate 200, the wireless IC chip300, the antennas 410, 420, the electronic devices 500 and a part ofeach terminal 600 to protect these parts and prevent the wireless module101 from being converted or disassembled. For instance, the resincoating 700 is made of black thermoplastic resin or thermosetting resin.

The resin coating 700 is formed by performing dip molding using powderedresin with respect to the substrate 200 on which a wireless IC chip 300,antennas 410, 420 and electronic devices 500 are mounted. In thisembodiment, after the substrate 200 on which the wireless IC chip 300and so on are mounted is heated, the substrate 200 is dipped intopowdered resin. In this process, the entirety of substrate 200 isdipped, with the terminals 600 or a frame (not shown) to which theterminals 600 are connected held. The powdered resin coming into contactwith the heated substrate 200 melts and adheres to the substrate 200 andso on. By repeating this process several times, the resin coating 700 isformed.

The advantages of the wireless module 101 are described below.

As shown in FIGS. 1 and 2, to mount the wireless module 101 of thisembodiment on a circuit board (an example of a mount object), the endsof the terminals 600 extending from the substrate 200 in the in-planedirection of the substrate 200 are connected to the circuit board S.This arrangement saves space in mounting the wireless module 101.

Mounting to the circuit board S by using the terminals 600 extending inthe in-plane direction of the substrate 200 allows the substrate 200 tobe spaced apart from the circuit board. This allows the parts such asthe wireless IC chip 300 or the electronic devices 500 to be mounted onboth surfaces 200 a and 200 b of the substrate 200. This contributes tosize reduction of the wireless module 101.

Since the antennas 410, 420 arranged on the substrate 200 are distantfrom the circuit board S, a high degree of freedom is provided withrespect to the three-dimensional arrangement of the antennas. Byarranging the antennas 410, 420 spaced apart from each other, the radiowave directivity can be widened, which enhances communication quality ofthe wireless module 101.

The antenna 410 extends in the direction y (horizontal direction in FIG.1), whereas the antenna 420 extends in the direction z (verticaldirection in FIG. 1). This arrangement allows the antenna 410 and theantenna 420 to have different radio wave directivities. This arrangementcontributes to enhancement of communication quality of the wirelessmodule 101.

According to the wireless module 101 of this embodiment, flow solderingcan be employed as a technique for mounting the module on the circuitboard S, which enhances efficiency of the mounting work.

FIGS. 3-8 show other embodiments of the present invention. In thesefigures, the elements that are identical or similar to those of theforegoing embodiment are designated by the same reference signs as thoseused for the foregoing embodiment.

FIG. 3 shows a second embodiment of a wireless module according to thepresent invention. The wireless module 102 of this embodiment differsfrom that of the first embodiment in structure of the terminals 600. Inthis embodiment, each of the terminals 600 is bent so that the regionfrom an intermediate portion to the end extends in the thicknessdirection of the substrate 200 (direction x).

To mount the wireless module 102 of this embodiment on the circuit boardS, the ends of the terminals 600 extending from the substrate 200 in thein-plane direction of the substrate 200 are connected to the circuitboard S. This arrangement saves space in mounting the wireless module102.

Each terminal 600 is bent so that the region from an intermediateportion to the end extends in the thickness direction (direction x) ofthe substrate 200. Thus, when the wireless module 102 is mounted on thecircuit board S, the substrate 200 faces the circuit board S with apredetermined distance from the circuit board S. This embodiment allowsarrangement of a ground plane on the circuit board S at a positionfacing the substrate 200. Thus, a high degree of freedom is providedwith respect to the arrangement of a ground plane, which contributes toenhancement of communication quality.

FIG. 4 shows a third embodiment of a wireless module according to thepresent invention. The wireless module 103 of this embodiment isprovided with a connector 220, which is the difference from that of thefirst embodiment.

The connector 220 is provided at an appropriate position on thesubstrate 200 and may be arranged close to the wireless IC chip 300.When a separately prepared antenna (not shown) is mounted on the circuitboard S, the connector 220 is used for connecting a terminal portionthat is to be connected to that antenna via a transmission line (notshown) for transmission/reception signals. The connector 220 isconnected to the wireless IC chip 300 via a transmission path (notshown) for transmission/reception signals. The transmission path, madeof e.g. a metal having a relatively low resistance, is a portion throughwhich transmission/reception signals pass. The transmission path may beprovided by a part of the wiring pattern. Alternatively, when thesubstrate 200 is a multilayer substrate, the transmission path may beprovided by a metal film pattern formed on the multilayer substrate.

The connector 220 is not covered by the resin coating 700 and exposed tothe outside. This arrangement is obtained by masking the connector 220in forming the resin coating 700.

To mount the wireless module 103 of this embodiment on the circuit boardS, the ends of the terminals 600 extending from the substrate 200 in thein-plane direction of the substrate 200 are connected to the circuitboard S. This arrangement saves space in mounting the wireless module103.

According to this embodiment, transmission/reception can be performedalso by an antenna provided separately from the wireless module 103.This arrangement is advantageous for enhancing communication quality ofthe wireless module 103.

FIGS. 5 and 6 show a fourth embodiment of a wireless module according tothe present invention. The wireless module 104 of this embodimentdiffers from that of the first embodiment in structure of the antenna asa transmitter-receiver.

In this embodiment, antennas 430 and 440 are provided on the substrate200. The antenna 430 projects from the first edge 211 of the substrate200 toward a first side in the direction z. The antenna 440 projectsfrom the second edge 212 toward a second side in the direction z. Theseantennas 430, 440 can be made of the same material as that of theterminals 600. The antenna 430 is bent so that the region from anintermediate portion to the end extends in the thickness direction ofthe substrate 200 (direction x). Although the antenna 440 is covered bythe resin coating 700 in this embodiment as shown in FIGS. 5 and 6, theantenna 440 may be exposed.

To mount the wireless module 104 of this embodiment on the circuit boardS, the ends of the terminals 600 extending from the substrate 200 in thein-plane direction of the substrate 200 are connected to the circuitboard S. This arrangement saves space in mounting the wireless module104.

The antenna 430 extends in the direction y (horizontal direction in FIG.6), whereas the antenna 440 extends in the direction z (verticaldirection in FIG. 6). This arrangement allows the antenna 430 and theantenna 440 to have different radio wave directivities. This arrangementcontributes to enhancement of communication quality of the wirelessmodule 104.

FIG. 7 shows a fifth embodiment of a wireless module according to thepresent invention. The wireless module 105 of this embodiment differsfrom that of the fourth embodiment in structure of the terminals 600. Inthis embodiment, each terminal 600 is bent so that the region from anintermediate portion to the end extends in the thickness direction(direction x) of the substrate 200.

To mount the wireless module 102 of this embodiment on the circuit boardS, the ends of the terminals 600 extending from the substrate 200 in thein-plane direction of the substrate 200 are connected to the circuitboard S. This arrangement saves space in mounting the wireless module105.

Each terminal 600 is bent so that the region from an intermediateportion to the end extends in the thickness direction (direction x) ofthe substrate 200. Thus, when the wireless module 105 is mounted on thecircuit board S, the substrate 200 faces the circuit board S with apredetermined distance from the circuit board S. The antenna 430 extendsin the direction x (vertical direction in FIG. 7), whereas the antenna440 extends in the direction z (horizontal direction in FIG. 7). Thisarrangement allows the antenna 430 and the antenna 440 to have differentradio wave directivities. This arrangement contributes to enhancement ofcommunication quality of the wireless module 105.

FIG. 8 shows a sixth embodiment of a wireless module according to thepresent invention. The wireless module 106 of this embodiment includes acase 230, which is the difference from mainly the first embodiment.

The case 230 is made of a metal and provided on the first surface 200 aof the substrate 200. The case 230 covers the wireless IC chip 300. Theantennas 410 and 420 are not covered by the case 230. The structureincluding the case 230 prevents radio signals from leaking from thewireless IC chip 300 to the outside.

The wireless module according to the present invention is not limited tothe foregoing embodiments. The specific structure of the wireless moduleaccording to the present invention can be varied in design in many ways.

Although a pattern antenna is described as an example of antennas 410,420 (transmitter-receiver) provided on the substrate 200 in theforegoing embodiments, the present invention is not limited to this.Other kinds of antennas such as a chip antenna may be employed as theantennas on the substrate.

1. A wireless module comprising: a wireless IC chip for processingtransmission/reception signals; a substrate on which the wireless ICchip is mounted; a transmitter-receiver at least a part of which isdisposed on the substrate; and a plurality of terminals extending fromthe substrate in an in-plane direction of the substrate.
 2. The wirelessmodule according to claim 1, wherein the substrate has a contourincluding a first edge extending in a second direction perpendicular toa first direction corresponding to a thickness direction of thesubstrate, and the terminals are arranged along the first edge, each ofthe terminals extending from the first edge toward a first side in athird direction perpendicular to both of the first and the seconddirections.
 3. The wireless module according to claim 2, wherein thetransmitter-receiver includes a first antenna provided on a firstsurface of the substrate, the first surface facing to a first side inthe first direction.
 4. The wireless module according to claim 3,wherein the contour of the substrate includes a second edge spaced apartfrom the first edge in the third direction and parallel to the firstedge, and the first antenna is arranged at a position offset toward thesecond edge in the third direction.
 5. The wireless module according toclaim 4, wherein the contour of the substrate includes a third edge anda fourth edge each of which is connected, at ends thereof, to the firstedge and the second edge, the third and the fourth edges being spacedapart from each other in the second direction and parallel to eachother, and the transmitter-receiver includes a second antenna arrangedat a position offset toward the third edge in the second direction. 6.The wireless module according to claim 5, wherein the first antenna isarranged at a position offset toward the fourth edge in the seconddirection.
 7. The wireless module according to claim 5, wherein thefirst antenna and the second antenna have different radio wavedirectivities.
 8. The wireless module according to claim 3, wherein eachof the terminals is bent so that a region from an intermediate portionto an end thereof extends in the first direction.
 9. The wireless moduleaccording to claim 8, wherein the end of each of the terminals faces toa second side in the first direction.
 10. The wireless module accordingto claim 3, wherein the wireless IC chip is mounted at one of a firstregion of the first surface of the substrate and a second region of asecond surface opposite to the first surface of the substrate, the firstregion excluding a region in which the transmitter-receiver is arranged,the second region overlapping the first region as viewed in the firstdirection, and the wireless module further comprises an electronicdevice mounted at the other one of the first region and the secondregion.
 11. The wireless module according to claim 2, wherein thetransmitter-receiver includes a third antenna projecting from the firstedge of the substrate toward a first side in the third direction. 12.The wireless module according to claim 11, wherein the third antenna isbent so that a region from an intermediate portion to an end thereofextends in the first direction.
 13. The wireless module according toclaim 11, wherein the contour of the substrate includes a second edgespaced apart from the first edge in the third direction and parallel tothe first edge, and the transmitter-receiver includes a fourth antennaprojecting from the second edge toward a second side in the thirddirection.
 14. The wireless module according to claim 11, wherein eachof the terminals is bent so that a region from an intermediate portionto an end thereof extends in the first direction.
 15. The wirelessmodule according to claim 11, further comprising a resin coatingcovering the substrate and the wireless IC chip.
 16. The wireless moduleaccording to claim 15, further comprising a resin coating covering thesubstrate and the wireless IC chip, wherein the third antenna is exposedfrom the resin coating.
 17. The wireless module according to claim 1,further comprising a case covering the wireless IC chip.
 18. Thewireless module according to claim 1, further comprising a connectorprovided on the substrate and connected to the wireless IC chip via atransmission path for transmission/reception signals.